I am sorry no-one has been able to help so far but it could well be no-one has seen this error before.
Certainly I have never seen this come up on the forum. It looks like a download error as I can't backtrack and find the last folder in that chain. The MGXAMIN~1 folder on-wards. It does not exist on my system. I doubt it has been 'cleaned' by me as I don't think the cleaning programs touch that temp area. You can see the Magix temp folder is still there but that is for the working installed program.
Does the missing location exist on your system?
Did you delay installing the program for any reason? Say to clear disk space on the C: drive to have enough space to install it? If so that action may have removed the folder and files but that is just guess from me rather than an educated answer.
Does the error message popup after the Download Manager is started or when the Download Manager has downloaded the main program and starts to install it?
What antivirus program are you using?
Your computer specification may also help - see this topic for what is required and please quote processor and graphics card make/model in full, and also what monitor/screen resolution(s) your are working with.
I would suggest you put this information in your profile signature so we do not have to keep asking for it.